Seagate Barracuda ES.2 1TB SAS Hard Drive

by Guest Sat Jun 07, 2008 2:54 am

Let’s talk about SCSI for a moment. The disk interface which was once ubiquitous with high-end workstations and servers is now on the verge of obsolescence. With the influx of inexpensive and reliable Serial ATA hard disks and hardware SATA RAID controllers (which can provide excellent performance at a fraction of a SCSI’s price), it’s not surprising to see why legacy SCSI doesn’t even enter the mind of enterprise server and workstation platform buyers, even those diehards of the past.

However, like PATA's evolution to SATA, SCSI has also gone the way of serial connectivity and it still holds its advantages. For example, 15K RPM hard disks are only available with a SCSI or SAS (Serial Attached SCSI) interface, and true hardware SAS RAID cards, when paired with 15,000 RPM disks, can deliver performance that SATA setups simply can’t deliver at this point in time. Not to mention the additional diagnostic, error reporting and recovery capabilities of SAS in a RAID set, that you just can't get in the event of a drive failure in a SATA RAID set. However, the price per gigabyte versus the performance that SAS offers over SATA simply hasn’t worked out in favor of SAS, and as such, the standard has been struggling to stay relevant. This is evident in the new generation of solid state hard drives (SSDs) being offered with SATA interfaces and not a hint of SAS SSD offerings on the horizon.

That said SAS solution providers seem to be reacting, as the barriers to entry for SAS versus SATA have been fading away as of late. SAS controller cards can be had for a little as $70, and SAS hard drives are dropping in price, though historically capacities have trailed SATA by a long shot. Also, some new motherboards offerings are being equipped with onboard SAS controllers as well.

Today, we’ll be showcasing one of the most significant developments to date, toward getting SAS more frequently into the vernaculars of workstation/server buyers and maybe even a few enthusiasts - relatively cheap, high-capacity SAS storage – thanks to Seagate. Seagate currently offers 10,000 and 15,000 RPM disks with SAS interfaces at a fraction of the capacity versus SATA offerings and as such, much higher prices. However, Seagate just launched their Barracuda ES.2 platform with a SAS interface that offers capacities up to 1 Terabyte (1 TB). Not only is the Barracuda ES.2 the highest capacity SAS disk to date, it’s also the first SAS disk we’ve seen on the market with a 7,200 RPM spindle speed and SATA-like pricing.

Seagate Barracuda ES.2 1TB SAS Hard Drive Es2small_1

A pair of Seagate's new Barracuda ES.2 SAS 1 TB drives.

Lower spindle speeds typically correlate to far lower prices per GB, and now with high-capacity disks available at more competitive prices, enterprise customers can mix and match their smaller (fast) SAS drives together with slower, but larger capacity SAS disks for bulk storage, on the same controller. In addition, this new large capacity Seagate SAS offering allows high-end or enthusiast end users to consider SAS for desktop builds. It’s definitely an interesting move by Seagate, that caught us by surprise a bit. However, here we are, with a pair of Barracuda ES.2 1 TB drives with SAS interfaces on our hands. Our job is to figure out where these drives fit into the workstation/server storage market that exists today and see if they represent a competitive value in comparison to the array of 1 TB SATA drives on the market. Let’s find out.

Seagate will be making the Barracuda ES.2 SAS drive in 500 GB, 750 GB, and 1.0 TB flavors, depending on the number of platters used in the drives. As expected, the Barracuda ES.2 is built on perpendicular recording technology, and features a 250 GB per platter density. These attributes are shared between the ES.2 SAS and SATA lineups, along with the Barracuda 7200.11 series drives.

by Guest Sat Jun 07, 2008 2:58 am

Upon first glance, the Barracuda ES.2 SAS looks like any standard 3.5" SATA hard drive. Visually, it’s hard to see any difference between the Barracuda ES.2 SAS and SATA models. However, upon closer inspection, one can see that the power/data connector is slightly different compared to what you would see with a standard SATA hard disk.

Seagate Barracuda ES.2 1TB SAS Hard Drive Big_210

Seagate Barracuda ES.2 1TB SAS Hard Drive Big_210

Seagate Barracuda ES.2 1TB SAS Hard Drive Big_310

SAS hard drives share the same physical cables as SATA hard drives, but they use a single connector which has data and power in a single connector. It’s pretty confusing for end-users to understand, but basically what you need to know is that SAS hard drives require SAS adapters in order to run in a desktop/tower chassis environment (adapters can cost anywhere from $10 - $50). In a rackmount environment, one can typically use SAS hard drives in standard SATA disk cages.

Seagate Barracuda ES.2 1TB SAS Hard Drive Small_4

SAS Interface on the Barracuda ES.2

Seagate Barracuda ES.2 1TB SAS Hard Drive Small_5

Promise TX2560 SAS Controller

For our tests, we used Promise’s new consumer-targeted TX2560 SAS controller card, which can be had for a mere $70 today (2 x SAS adapters included). Most SAS cards with hardware RAID prcessors price out in the $300+ range, so seeing affordable SAS adapters is definitely exciting to see. Not surprisingly, such a product only provides the very basics for a SAS disk setup, including support for two SAS 3GB/s or SATA-II/300 drives, a PCI Express x1 interface, and support for RAID 0, 1 and JBOD modes. The card utilizes the Promise PDC42819 controller, which is a software-based solution, meaning there is no dedicated RAID processor onboard. However, with only two ports, the need for hardware RAID processing is slim, and the increased latencies of such a solution might hurt single/dual disk performance. We’re just glad to see something finally filling up those PCI Express x1 slots which sit empty on so many of today’s motherboards.

The Barracuda ES.2 1TB SAS drives are nearly identical to their SATA-equipped Barracuda ES.2 brethren. Both the Barracuda ES.2 SATA and SAS drives support up to 1 TB of storage capacity and are housed in a standard 3.5" form factor. Both drives have 7,200 RPM spindle speeds, and both are equipped with 5 year warranties. Both the SATA and SAS variants can sustain 105 MB/s transfer rates at their peak. There are differences, however - and one is somewhat of a major one. For reasons unknown, Seagate decided to strip down the SAS variant and only offer it with 16 MB of cache, whereas the SATA variant has a larger 32 MB of cache on the high-end models. The SAS version also consumes a bit more power, although the difference is a somewhat trivial 1W.

by Guest Sat Jun 07, 2008 3:01 am

Seagate Barracuda ES.2 1TB SAS Hard Drive 1210

The Barracuda ES.2 SAS has a few competitors – namely Seagate’s own ES.2 SATA product line which has similar features but a different connector, more cache, and will (likely) sell at a lower price point. Potential buyers will likely be interested in how the drive compares to other similarly classed high-capacity drives. However, in the land of truly high-capacity SAS storage, the Barracuda ES.2 SAS stands alone, as its closest competitor has less than 1/3rd the capacity (300 GB) and costs about three times as much as the ES.2.